The pockmark stars: radial structures in the seabed surrounding the Hawaii Islands

OPEN ACCESS This open-access article is distributed under the terms of the Creative Commons Attribution Non-Commercial License (CC BY-NC) (http:// creativecommons.org/licenses/by-nc/4.0/), which permits reuse, distribution and reproduction of the article, provided that the original work is properly cited and the reuse is restricted to noncommercial purposes. For commercial reuse, contact [email protected] T Hawaiian Islands are an example of an age-progressive chain formed by the movement of the Pacific plate over a rise of a thermal plume from the lower mantle (1). The classic concept of plume, fed by a hotspot more or less fixed in the mantle, which explains Hawaiian volcanism, is questioned by unclear phenomena: the variation of volcanic material erupted over time, asymmetric distribution of the geochemistry of the lava and secondary volcanism occurring in distant areas of the hotspot. These phenomena have been explained by a “small-scale” convection in the mantle that erodes the base of the lithosphere and generates localized lifts distant from the hotspot (2). Although the main feature of a volcanic chain is the presence of a high bathymetric associated with an abnormally warm mantle, these factors were not found in the seabeds surrounding the volcanic chain of Hawaii. In addition, the previous estimates of the maximum crost size below the Hawaii Islands are in the range of 15 to 20 km (3), while the average thickness in the areas surrounding the swell is about 6.2 km (4).